States admitted and territories organized

Party summary

The count below identifies party affiliations at the beginning of the first session of this congress. Changes resulting from subsequent replacements are shown below in the "Changes in membership" section.

Senate

During this congress, two Senate seats were added for the new state of Indiana.

Members

Senate

Senators were elected by the state legislatures every two years, with one-third beginning new six year terms with each Congress. Preceding the names in the list below are Senate class numbers, which indicate the cycle of their election. In this Congress, Class 1 meant their term began with this Congress, requiring reelection in 1820; Class 2 meant their term ended with this Congress, requiring reelection in 1816; and Class 3 meant their term began in the last Congress, requiring reelection in 1818.